Question

I have a table like

tbl_scripts

script_unique_id | system_id | script_name
+-----------------------------------------+
12345            |  89784    |   Demo

And another table goes as

tbl_allowed_group_ids

system_id | script_unique_id |allowed_group_id
+---------------------------------------------+
89784       12345             56987

So now what I want is the row from tbl_scripts with group_id only if the unique id is in allowed_group_id

What I tried is this but is nowhere close to it….I know this is completely wrong

SELECT script_name FROM tbl_scripts WHERE script_unique_id = allowed_group_id

Answer 1

You will want to JOIN the tables:

select *
from tbl_scripts s
left join tbl_allowed_group_ids g
  on s.system_id = g.system_id 
  and s.script_unique_id = g.script_unique_id 

See SQL Fiddle with Demo

If you need help learning join syntax, here is a great visual explanation of joins.

A LEFT JOIN will return all rows in the tbl_scripts table regardless of whether or not it has a matching row in the tbl_allowed_group_ids table. If you only want matching rows, then you can use an INNER JOIN